package org.apache.rocketmq.console.config.intercepter;

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
import java.nio.charset.Charset;

/**
 * 保存流
 *
 * @author yefuliang 2017年10月25日
 */
public class BodyReaderHttpServletRequestWrapper extends HttpServletRequestWrapper {
	private final byte[] body;

	public BodyReaderHttpServletRequestWrapper(HttpServletRequest request) throws IOException {
		super(request);
		String sessionStream = getBodyString(request);
		body = sessionStream.getBytes(Charset.forName("UTF-8"));
	}

	/**
	 * 获取请求Body
	 *
	 * @param request
	 * @return
	 */
	public String getBodyString(final ServletRequest request) {
		StringBuilder sb = new StringBuilder();
		InputStream inputStream = null;
		BufferedReader reader = null;
		try {
			inputStream = cloneInputStream(request.getInputStream());
			reader = new BufferedReader(new InputStreamReader(inputStream, Charset.forName("UTF-8")));
			String line = "";
			while ((line = reader.readLine()) != null) {
				sb.append(line);
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (inputStream != null) {
				try {
					inputStream.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (reader != null) {
				try {
					reader.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
		return sb.toString();
	}

	/**
	 * Description: 复制输入流</br>
	 *
	 * @param inputStream
	 * @return</br>
	 */
	public InputStream cloneInputStream(ServletInputStream inputStream) {
		ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
		byte[] buffer = new byte[1024];
		int len;
		try {
			while ((len = inputStream.read(buffer)) > -1) {
				byteArrayOutputStream.write(buffer, 0, len);
			}
			byteArrayOutputStream.flush();
		} catch (IOException e) {
			e.printStackTrace();
		}
		InputStream byteArrayInputStream = new ByteArrayInputStream(byteArrayOutputStream.toByteArray());
		return byteArrayInputStream;
	}

	@Override
	public BufferedReader getReader() throws IOException {
		return new BufferedReader(new InputStreamReader(getInputStream()));
	}

	@Override
	public ServletInputStream getInputStream() throws IOException {
		final ByteArrayInputStream bais = new ByteArrayInputStream(body);
		return new ServletInputStream() {
			@Override
			public int read() throws IOException {
				return bais.read();
			}

			@Override
			public boolean isFinished() {
				return false;
			}

			@Override
			public boolean isReady() {
				return false;
			}

			@Override
			public void setReadListener(ReadListener readListener) {
			}
		};
	}
}
